1. Field of the Invention
The present invention relates to an electric welding torch generally and particularly to torches adapted for use in the MIG, TIG and plasma welding processes. In welding processes of the type described, a welding torch is provided for holding a non-consumable electrode generally of thoriated tungsten or other appropriate material and an electric arc is generated between the end of the electrode and the work piece with the arc being shielded by a gas of suitable type passed around the arc from the torch.
2. Description of the Prior Art
Electric welding torches employing non-consumable electrodes and useful in the MIG, TIG and plasma welding processes from time to time require replacement and/or adjustment of the position of the non-consumable electrode used in the torch. In prior torches, various different means such as radially split annular clamping rings have been used for holding the electrode in place during the welding process. Many prior art torches suffer from the difficulty of requiring too much operator time for making replacement of a non-consumable electrode or for position adjustment of the electrode in the torch as the electrode is gradually eroded away during the welding process. Many prior art torches utilize electrode clamping systems for holding and making electrical contact with the electrodes which do not readily lend themselves to providing suitable high amperage electrical contact with the electrode. In addition, these torches do not provide an efficient gas passage for the shielding gas as it flows out towards the outer end of the electrode to form a shield around the welding arc. Many prior art welding torches are mechanically complex, expensive, and do not have a capacity to provide a high current density when a minimum diameter electrode is used. Moreover, often times replacement or adjustment of the position of the electrode is difficult and cumbersome.